As an alternative to physically surveying regions of interest such as a forest tract, etc., many landholders are using remote sensing technology to aid in forest management. Such remote sensing technology can be used to assess the number of trees in a region of interest, as well as estimate their average height, age, market value and other information. One widely used remote sensing technology is light detection and ranging (LiDAR). With LiDAR, an aircraft is flown over a region of interest and a transmitting and sensing unit on the aircraft directs laser pulses towards the ground. The laser pulses that are reflected from vegetation and/or the ground are received by a detecting unit. Because the speed and altitude of the aircraft are known, the round trip time for each pulse provides a 3 dimensional coordinate for each reflected pulse. The coordinates can be combined in a computer to produce a topographical map of the region of interest.
One problem with analyzing LiDAR data is being able to determine which LiDAR data points are associated with individual trees or other items of vegetation in the region of interest. One technique for doing so is disclosed in U.S. Pat. No. 7,474,964 (“'964”), which is herein incorporated by reference. In the '964 patent, digital umbrellas are defined for LiDAR points. Those LiDAR points that are located within an overlapping digital umbrella area of a higher point are presumed to be associated with the same item of vegetation. While the technique described in the '964 patent works well, improvements can be made to individual items of vegetation, e.g., trees or other objects in a region of interest.